Many devices such as personal computers (“PCs”), personal digital assistants (“PDAs”), embedded devices, etc., contain processors or controllers and associated hardware and software. When a device containing a processor or controller is powered a startup sequence or boot process is triggered. This boot process is generally a series of steps executed by the device to load the operating system. The steps that occur during this boot process may be hardware and software dependent, but generally result in the processor displaying to a user that the system is ready for user input.
A typical boot process includes a power on self test where the device tests its memory, verifies that it has the necessary hardware (e.g., a keyboard, video display, mouse, etc) and allows other peripherals (e.g., adapter cards, printers, etc) time to run their own self tests. The device may then load a Master Boot Record (“MBR”) into memory, which in turn locates the active partition and loads the boot sector into memory (for a device with a hard disk). The next series of steps chooses the operating system (“OS”) to run on the device. The steps may include switching the processor into a different memory mode (e.g., from real mode to a 32-bit flat memory mode), starting the appropriate file system to read files from a hard disk or flash memory, selecting the OS and gathering information about the device hardware. The next series of steps may be to select the hardware configuration and control set for the current boot and load the appropriate device drivers for the configuration. A session manager may then be started which runs programs listed in a boot registry and the starting of required subsystems. Finally, a logon prompt may appear, to which the user will respond with the appropriate command.
Similar to the boot process described above, when an application program or development software is started on a device, a series of steps may be carried out to start different pieces of software for the processor to carry out the commands directed by the application software. Such pieces of software may be referred to as plug-ins, tools, objects, etc.